1. Field of the Invention
The present invention relates to a producing method for a liquid discharge head (hereinafter also called “ink jet recording head”) which discharges a liquid by applying an energy to the liquid.
2. Related Background Art
Recently, an ink jet recording apparatus is widely utilized, because of a satisfactory recording property and a low cost thereof, as an output apparatus of personal computers. Among such ink jet recording apparatus, there are being developed, for example, a type which generates a bubble in an ink by a thermal energy and discharges an ink droplet by a pressure wave caused by the bubble, a type which discharges an ink droplet by an electrostatic attraction, and a type utilizing a pressure wave caused by a vibrator such as a piezoelectric element.
Among the aforementioned ink jet recording apparatuses, the type utilizing the piezoelectric element has a configuration including an ink flow path communicating with an ink discharge port and a pressure generation chamber communicating with the ink flow path, in which a piezoelectric thin film, provided in the pressure generation chamber and adjoined to a vibration plate film executes an elongation-contraction when given a predetermined voltage whereby the piezoelectric film and the vibrating plate film integrally cause a vibration to compress an ink in the pressure generation chamber, thereby discharging an ink droplet from the ink discharge port.
In recent ink jet recording apparatus, improvements in the recording performance, particularly a high resolution and a high-speed recording, are being requested. For meeting such requirements, it is necessary to reduce a discharge amount of the ink droplet discharged at a time, and to execute a high-speed drive. For attaining these, Japanese Patent Application Laid-open No. 9-123448 discloses a method of reducing a volume of the pressure generation chamber, in order to reduce a pressure loss therein.
Also, though for a different purpose, Japanese Patent No. 3168713 discloses an ink jet head in which a silicon substrate having a surface orientation {110} is employed as a substrate and a {111} plane of such substrate is positioned on a lateral face of the ink pressure generation chamber. Also Japanese Patent Application Laid-open No. 2000-246898 discloses a head in which piezoelectric elements are provided in an area opposed to a cavity formed in a silicon substrate to secure rigidity of a partition between pressure generation chambers, thereby preventing a crosstalk phenomenon.
In the prior technology, it has been difficult to prepare a pressure generation chamber of a small volume in a simple process. Also a complex process is required for forming a thin vibrating plate. Because of these reasons, it has been difficult to produce an ink jet recording head, utilizing a piezoelectric thin film in a discharge pressure generating element, in an integrated state of a high density.
Also in a method for producing a piezoelectric element disclosed in Japanese Patent Application Laid-open No. 2000-246898, since the vibrating plate is hollow and bent by a large angle, a stress concentration may result in a part thereof, thus deteriorating the durability. Also as the element protrudes in the liquid chamber, there may result an increase in the resistance of the flow path, thus detrimentally affecting the discharge frequency.